1. Technical Field
The present invention relates to an optical waveguide film and a method for producing the same.
2. Related Art
An optical waveguide needs to be connected to a light-emitting/receiving device, optical fibers, or other optical waveguides. Therefore, it is preferable that the position of the core of the optical waveguide and the position of an end surface of the core be accurately recognized. However, waveguide cores and waveguide claddings are both transparent. Connection of an optical waveguide to light-emitting/receiving elements, optical fibers, or other optical waveguides can be made easier by separately providing an easily-detectable mark for positioning that has a fixed positional relationship relative to the end surface of the core. A mark for positioning enables accurate detection of the position of the optical waveguide core, and may take a form of plural minute (comparable to the size of the cross-section of the optical waveguide core) cross-shaped marks provided at the optical waveguide.
In order to accurately set the positional relationship between the mark for positioning and the end surface of the optical waveguide core that is to be connected to an external element, it is preferable to simultaneously form the mark for positioning and the core pattern using a core pattern forming process. This technique has been used in conventional methods for producing optical waveguides.
An optical waveguide production method exists that does not use a photomask or a template. In this method, an optical waveguide core is formed by cutting a flexible optical film with a dicing saw. This production method can be applied to formation of an optical waveguide having a large number of linear-array waveguide cores, such as an optical bus for high-speed data transmission between boards. Cutting using a dicing saw is effective in cost reduction since it enables realization of a fast processing.